Electrolyte and device employing the same



June 15, 1937. J E 2,084,046

ELECTROLYTE AND DEVICE EMPLOYING THE SAME Filed Jan. 20, 1932 Jam 20506;

June 15, 1937 NITED STATES ELEGTROLYTE AND DEVIGE EMPLOYING THE SAMEJohn T. Owen, Chicago, Ill., assignor, by meme assignments, to Tang-SolLamp Works Inc., Newark, N. .L, a corporation or New York ApplicationJanuary 20, 1932;, Serial No. 587,678

26 Claims.

is known as a Wet electrolytic condenser, and

others provide a gel electrolyte to form what is known as a dryelectrolytic condenser. The improved electrolyte of my invention may beem ployed in both wet and dry electrolytic con- 15 densers.

Heretofore electrolytic condensers have been suitable for use only onrelatively low voltages, because of the relatively low peak voltagesthat the oxidized films were capable of withstandg ing when in contactwiththe e1ectrolyte.- The electrolytes employed have inherently had arelatively low conductivity which heretofore has been improved somewhatat the expense oi increased power factor loss in the condenser. 5 In aperfect condenser the current leads the voltage by 90 degrees and. isentirely wattless, that is, there is no component of the current inphase with the voltage. Theoretical condensers of this type are, ofcourse, impossible of realization, and because of dielectric losses inthe condenser the current does not lead the voltage by 90 degrees butrather lags several de= grees behind this theoretical value. This results in a component of the current in phase 5 with the voltage and aconsequent power loss in the condenser. In electrolytic condensers ofthe prior art, when the electrolyte is treated tc increase itsconductivity in the direction of a lower pH value and consequently toincrease the maidmum peak voltage upon which the condenser cansatisfactorily operate, there has been a corresponding increase in powerloss in the condenser occasioned by further lagging oi the currentbehind the theoretical 90 degrees maximum.

My improved electrolyte permits operating the condenser upon higher peakvoltages than have been possible heretofore, and at the same timepermits operation at this voltage without material increase in the powerloss in the condenser. That is, with my improved compound I am able toincrease the peak. voltage of the condenser without incurring aconsequent increase ln power factor and loss. The phase angle ofcondensers employing my improved electrolyte has been found to be withinnot over 6 of the theoretical maximum.

Dry electrolytes of the prior art of which ll am. aware are incapable offorming an oxide film upon the metallic plate of the condenser.

60 In the manufacture of these condensers the films are formed in aseparate bath prior to coming into contact with the electrolyte oi thecondenser. As a result if the oxide film on the plate contains a smallimperfection, such as a pin hole, and that imperfection breaks down dur=ing the operation of the condenser, the hole or fault increases untilthe condenser actually becomes short circuited and worthless. With myimproved electrolyte, employed in contact with a film of oxide formed asheretofore, should an imperfection occur in the iilm and the metal ofthe plate thereby be exposed to the electrolyte, a new film of oxidewill be formed by the electrolytic action of the electrolyte upon theplate when the condenser is in use, and the im perfection will bereduced rather than increased in severity. My improved electrolyte iscapable of forming a suitable coating of oxide upon a metallic plate,should an occasion arise in which it would be advantageous to form theoxide film in this manner. Condensers built with my lin provedelectrolyte have a long sheli life, that is, they may be stored indisuse for a long period of time without the electrolyte destroying anyfilm present on one electrode or forming a film on the other electrode,and without deteriora= tion 01' the electrolyte.

in the drawing:

Figure l illustrates my invention adapted to a condenser for use indirect or intermittent al-= ternatlng current circuits; and

Figure 2 illustrates my invention applied to a condenser for use indirect or intermitmnt al ternating current circuits.

in its preferred form my invention provides an electrolyte compoundedfrom hydrony-allryl amines such as a monoethanol amine indicated by theformula.

or varying mixtures of two or more of these combined with an acid in thesame manner as any hydroxide such as ammonium hydroxide, sodiumhydroxide, potassium hydroxide, etc, combines with acids. Although theamines have been above designated by trivalent nitrogen, it is to beunderstood that they are analogous to ammonia as a gas indicated asNl-Is, and in soiii the latter iorr uitro- Eentavalerrt. corohin ti minewith acicl a tri on of a trl ethanol amine l or sapooifiable oil sucholeic stearic calnut acicls, linoleic acid, riclnoleic acicl, acrylicacicl, etc, is as follows:

+a fatty acirl=a soap, producing ethanol amine soap. It -s of course tohe und rstood. that the monoarm. the cli-hyclrouy allzyl amines react inthe same Way as above indicateol for tri-ethanol amine.

The electrolytic salts of the hydroxy alkyl amines are active inredients of the electrolyte. The pH value of any salt of this characteris deter mined largely by the character of the acid component of theElectrolytic acids such as boric, tartaric, malic, citric, acetic andthe like give a low pH value. The hyclroxyl alkyl amine salts of suchacids are gels in structure. Uther acids, such as the fatty acics abovereferred. to, also have a low 10H value, and their hydroxy allcyl aminesalts are also gels in structure. The hydroxy allryl amines are alkalinein character and; have a pol-ll value higher than the acids alcovenamed.

In the present invention I form sal the electrolytic type of acids or oith anti the el ctrolytic type. I may i stances have excess or thehydroxy allsyl amine present l'l a free form to give a high pll value tothe melt-ore, or It may have an excess of either type or hoth types ofacicl present to give a lower value o the mixture. The fatty acid. saltsof the hyclroxy aliryl airlines are not necessary for the electrolyticfunctioning of the conductive salts, but they are oi such a physicalcharacter as gels, 9' cl substantially harmless, so they may eadvantageously useci as clilueuts or carriers fol "1e electrolytic saltsor the free eleo trolytic acicls, or or the hydroxy allryl amine,

Where that may present. Electrolyte value loelovv 7,. also may he somade to have are gel-li e i form. Such mixtures hygroscopic. They maylike on more than ours weight n ater will hold against drying out Toyordinary exposure. holding of such Water, however, does not desirablegel form of the electrolyte. ioi having small amounts of water resembleortii soap in their prooerty of resisting low ancl it cozingtemperatures without change. Temperatiues as low as -5il may he reached:Without dam- The electrolyte is will withstand. high peak voltages.

The electrolyte of my iuvention also he made by first combiningapproximately ecual molecular weights of a mono, a l or tri ethanol crme or mixture of two or more of these and. a tasty acid or saponifialolesubstance to produce a resultant salt. To this I add horic acid. whichwill bring the pH value below 7 to form the electrolyte. As before, theresulting product is a gel highly conductive and he used in a liquidelectrolytic condenser su ficie distilled Water is aclclecl to bring thesuost the proper viscosity as a colloidal solution. tinguishahle from acolloidal gel. lr since any of the hyclroxy allsyl amine se an extremelyhigh hygroscorzicity, they tain their original moisture content the lifeof the device in which the c l Boris acicl Mono ethanol amine Oleio acidSL129 Water i -30 The alcove composition is sufficiently liquid incharacter for use in a wet electrolytic condenser. By using the sameproportion of ingredients and omitting the added Water the compositionis a gel useful for olry electrolytic condensers. Varying the amount ofWater is one Way of regulating the character of the product physicallyas to form.

The composition may also be made by the following example formulas:

Formula 1 Percent Hyclrczry alkyl amine 25 Boric acid l 25 Fatty acicl.s 28 fv'ater N 86 The above composition is a of dilution with moreWater.

plastic gel capacle Formula 2 lvlozio-hyclroxy ethanol airline Tartaricacicl Formula t Tri hyrlrouy ethanol amine Malic aciol -l c Ste ric a;-l Water :36

This compounds is also a plastic l dilution W h more Forum-la e hyrlroxyethanol arnihe l l a 3!) Boris W 30 ii 'ater .L

This forms plastic with more water and s or fatty acicl.

Formula 5 Percent A hyriroxyhutanol amine Boric acid Stearic acicl"Water l N Evil More or less Water may be employed. to control theliquid or gel character clesireri.

In rnakirr these compounds the electrolytic acid and the hydroxy allzyiamine are mixed. The electrolytic acids are crystalline in structure,and they may contain Water of crystallization. The hydroxy alkyl are go.erally syrupy liquids miscible with water, and the commercial formsusually contain some water. be used in anhydrous form. Upon mixing anexothermic reaction results forming the gel or a solution of the gel.The fatty acid may be added to the resulting mixture either hot or cold.All or part of the fatty acid unites with any excess of the hydroxyalkyl amine and when an excess is used it assures that no alkalinecondition results. For the preferred use of the invention, as incondenser electrolytes, sufficient acid, of one kind or another, must beadded to prevent the presence of uncombined hydroxyallsyl amine. Theamount of water concerned in the reaction is immaterial except as acontrol of the physical character of the product.

The resulting electrolyte formed by combining hydroxy alkyl amine with asuitable acid such as boric acid is non-corrosive current. When used asabove described in a condenser with current, it is advantageouslycapable of forming the positive plate of an electro-= lytic condenserfrom pure metal, such as aluminum, for example, and for this reasonthere is no tendency for the electrolyte to disintegrate the oxidizedfilm on that plate however it be formed. The particular proportions ofhydroxy alkyl amines and acids employed in the manulecture of myimproved electrolyte may be varied over a considerable range withoutmaterially altering the characteristics of the electrolyte. This factrenders the electrolyte particularly advantageous for commercial usesince it can be successfully manufactured by relatively inexperiencedworkmen with a uniformly high uality of the product resulting. The costof manufacturing the electrolyte is very low.

Condensers employing hydroiry allryl amine salt as an electrolyte show aresistance value of as high as 650 megohms per mlcroiarad, a phase angleof within 5; degrees oi the theoretical max imum and a safe peak voltageof 550 volts. By using this electrolyte in a condenser having two oxidefilm formed plates, a device is formed which can be used advantageouslyfor power factor cor rection on low voltage A. (C. currents, such as 110volts. Condensers with single formed anodic films, and condensers withtwo formed plates have a multiplicity of uses well known to the art andthe present electrolyte may be advantageously used in such condensers.The cost of such condensers is relatively low as a result or? therelatively low cost of the electrolyte.

The electrolyte as a gel, may be used between the two plates of acondenser when those plates are planar surfaces or when they are formedas a series of convolutions. in Figure l l have diagrammaticallyillustrated such construction, applied to a condenser designed fordirect current work. In this condenser the negative plate 9, or plates6, comprisesbase metal, preferably aluminum. No oxide iilm is formed onthis plate. The positive plate 2 is suitably treated to coat it with anoxide film indicated at t. Separators d may be inserted between theplates 6 and ii to provide mechanical separation, this beingparticularly advantageous in case the plates are formed convolute.Preferably the separators are iormed of a foraminous, or porous, orabsorptive substance, such as cloth or paper. The electrolytic gel llsaturates these separators l and fills the voids between the plates andin fact surrounds the plates. is encased in a suitable housing, notshown, and

the plates are rendered accessible by lead out They may in the absenceof The condenser thus formed.

wires 6 and l which extend out of the casing. The condenser shown hashigh capacitance per unit volume, r

The electrolyte as a gel may be used to form an electrolytic condenserfor use in alternating current circuits. Such a constructionisdiagrammatically illustrated in Figure 2 of the drawing. This condensercomprises plates Ill and M, containing films i2 and I3 respectively. Theplates may conveniently be aluminum and the films aluminum oxide Aforaminous separator it may be used to mechanically separate the plates.This separator is saturated with the electrolyte is which fills thevoids between the plates and surrounds them. The condenser is housed ina suit able casing, not shown, from which lead out wires it and illextend to connect the plates ill and M to the external circuit. Such acondenser has high capacitance per unit volume, high resistance and canbe successfully operated on high peak voltages. The films are notdeteriorated by the electrolyte when the condenser is disconnected fromcurrent for long periods of time. When current fiows through thecondenser, the films are built up rather than destroyed.

While my improved electrolytic compound is intended primarily for use asan electrolyte in an electrolytic condenser, it may also be used as anelectrolyte in an electrolytic lightning arrester or protecting device,and for many other purposes. I am not, therefore, to be limited to thespecific use of the compound herein described by way of example.

What I consider new and desire to have protected by Letters Patent ispointed out in the appended claims.

What I claim is:

1. An electrical device comprising a iilm-forming metal electrode incontact with an electrolyte comprising as the essential ingredient saltof hydrouy allsyl amine and weal: electrolytic acid.

2. An electrical device comprising a film-forming metal electrode incontact with a liquid electrolyte comprising in solution as theessential ingredient salt oi hydroay alltyl amine and weal; electrolyticacid.

3. an electrical device comprising a fllhl-fOl'm-= ing metal electrodein contact with a gel elsetrolyte comprising as the essential ingredientcolloidal gel of salt of hydroiry allryl amine and weal: electrolyticacid.

l. An electrical device comprising a film-forming metal electrode incontact with an electrolyte comprising the reaction products of amixture of fatty acid, wealr electrolytic acid, and hydroxy allrylamine.

5. All electrical device comprising a film-forming metal electrode incontact with'an electrolyte comprising the reaction products of aquantity of hydroxy allryl amine completely neutralized with addedwealr. electrolytic acid.

6. an electrical device comprising a film-forming metal electrode incontact with an electrolyte comprising the reaction products of aquantity oi hydroxy alkyl amine completely neutralized with added weakelectrolytic acid and fatty acid.

7. An electrical device comprising a film-forming metal electrode incontact with an electrolyte comprising a mixture of salts of hydroxyallryl amine and weak electrolytic acid and oi hydroxy allryl amine andfatty acid.

8. An electrical device comprising a film-forming metal electrode incontact with an electrolyte containing essentially electrolytic salt ofhydroxy allryl amine and weak electrolytic acid, and con-- selected incan? devic

